Hi guys need some help going to get 400/400 on my FQ300 Evo X, the question is will i need a Uprated Fuel Pump? Because a few people has said no and a few has said yes.

 

They've said that because you'd be borderline. I wouldn't advise pushing the stock pump that hard when a Walbro 255 can handle 500 without a problem.

 

This.

If you're talking 400 WHP, the stock pump will probably barely be able to deliver that at 25 psi boost pressure. 400 bhp, absolutely yes - that only requires 180 L/h fuel flow or so, which the stock pump delivers all the way to 80 psi.

 

Uprated?

The 255's are cheap no reason not too.

 

I would, I already upgraded my fuel system and I'm not even close to that.

 

Stock pump is way more capable than most people think.

440whp on dynojet here, stock fuel system w/ dw800's.

 

wow impressive for a stock pump.

Thanks for the info

 

IDK why people don't already know this AMS published this very valuable info a LONG TIME AGO!



ASK yourself, how much power will a standard walbro 255 support? (dynojet)
550-600whp on gasoline
450-500whp on E85

Now figure based on the above data that the stock X fuel pump flows about 85% of a 255 and you get:
470-510whp on gasoline
382-425whp on E85

These are damn good numbers! I still say most people upgrade way too early and this is why.

Now figure don't even crack the seal of the tank and throw a boost-a-pump on it and you can expect an extra 20% flow. At this point you'd be at the limit of a basic walbro anyways, so mod one (a wally) then throw it in and you're good to go for some pretty serious power on a single pump w/o too fancy of a setup.



Now with the stupid adapter kits you need for the X. $150 is the cheapest one IIRC? + another $80-100 for the pump, that's $250-300 you could have spent on a set of injectors or other mods

 

Most people pay their tuner $150/hr, have to take time off of work, and have to schedule an appointment a few weeks (or longer out). They don't want to run out of fuel on the dyno if they can help it.

Your 440 was also on race gas, which requires less fuel per hp than pump. I've heard of people running out anywhere from low 400's to high 400's depending on the dyno. Given the choice I'd rather have a little headroom if I were shooting for 400 wheel.

The Boost-A-Pump costs as much as a pump kit. Single Walbro kits are pretty easy to install. I'd probably do that rather than mess with wiring. Not sure if the above chart is with a punched pressure relief but I've seen charts showing that a 255 can flow as much as an 044 (at 75psi) once modified.

It's quite possible that the OP was talking 400 crank, which is often the case in the UK. The stock pump would be fine for that.

 

400 BHP not WHP.

 

Isn't that the same thing??? Crank horsepower is different tho.

 

Walbro 255 just to be on the safe side.